Dispensing of viscous material

ABSTRACT

A dispensing mechanism places a predetermined quantity of a highly viscous paste into successive articles, such as battery grids. A constant level of the paste is maintained in a cylindrical dispensing cup of the mechanism, which has a gridlike bottom formed of radially disposed wires. The paste flows out of the grid-like bottom of the cup during vibration of the cup. When the vibration stops, the flow of the paste through the wires also stops. Thus, a convenient mechanism is provided for controlling the amount of paste dispensed.

United States Patent [191 Haller et a1.

[ DISPENSING OF VISCOUS MATERIAL [75] Inventors: Albert H. Haller,Clark, N.J.; John J. Larkin, Little Neck, N.Y.; Richard P. Walters,Watchung, NJ.

[73] Assignee: Western Electric Corporation, New

York, NY.

22 Filed: Sept. 7, 1971 21 Appi. No.: 178,133

[52] US. Cl 222/1, 222/189, 222/196,

' 141/32, 136/67 [51] Int. Cl. HOlm 35/26 [58] Field of Search 222/196,189, l;

[56] References Cited UNITED STATES PATENTS 3,259,272 7/1966 Larson 1.222/196 X Jan. 1, 1974 9/1939 Damond 222/196 8/1967 PrimaryExaminer-Robert B. Reeves 7 Assistant ExaminerFrederick R. HandrenAtt0rneyW. M. Kain et a1.

[5 7] ABSTRACT A dispensing mechanism places a predetermined quantity ofa highly viscous paste into successive articles, such as battery grids.A constant level of the paste is maintained in a cylindrical dispensingcup of the mechanism, which has a grid-like bottom formed of radiallydisposed wires. The paste flows out of the grid-like bottom of the cupduring vibration of the cup. When the vibration stops, the flow of thepaste through the wires also stops. Thus, a convenient mechanism isprovided for controlling the amount of paste dispensed.

7 Claims, 12 Drawing Figures Proskauer 222/199 X PATENTE JAN 1 2914 saw2 ur DISPENSING OF VISCOUS MATERIAL BACKGROUND OF THE INVENTION 1. Fieldof the Invention The invention relates to dispensing of material. Moreparticularly, the invention relates to the dispensing of controlledquantities of viscous pasty material.

2. Description of the Prior Art The introduction and development ofcylindrical lead-acid batteries of the type described in U.S. Pat. No.3,434,833, issued to I... D. Babusci et al. on Mar. 25, 1969, hasresulted in a need for refined manufacturing techniques which haveheretofore not been available. Previous designs of battery grids werequite amenable to conventional pasting techniques. However, the conicalconfiguration of the battery grids illustrated in the subject patentresults in a set of peculiar problems.

These problems are further complicated by the nature of the batterypaste utilized in the subject cylindrical batteries. This paste,tetra-basic lead sulfate, is a highly successful material for purposesof contributing to long life of the cylindrical batteries. However, thepaste is an extremely difficult substance to handle from abattery-manufacturing: point of view.

It is desirable to place a precise amount of the paste onto a batterygrid just prior'to the time that the battery grid is subjected to apasting operation of the sort which is described in patent application,Ser. No. 831,001, filed in the names of H. E. Durr and A. H. Haller onJune 6, 1969 and assigned to the assignee of record of this application.

Obviously, a proper quantity of paste can be placed on the gridsmanually. But manual dispensing of paste is cumbersome and uneconomicaland, therefore, un desirable in a well-designed manufacturing scheme.

Other conventional dispensing mechanisms are usually capable of placingonly an undistributed glob of the paste material onto a grid. Such anundistributed quantity of material presents difficulties in the pastingoperation disclosed in the aforementioned patent application.

SUMMARY OF THE INVENTION It is, therefore, an object of this inventionto efficiently dispense material.

It is another object of this invention to provide a system fordispensing a controlled quantity of viscous material onto an article.

It is a further object of the invention to accomplish such dispensing ofa materialin such a way that the material is uniformly distributedacross the surface of the article.

These objects are achieved by holding a volume of the material in ahopper having a grid portion with openings therein small enough topreclude free flow of the material therethrough when the material isstatically held in the hopper but with the openings large enough topermit flow of the material when the material is subjected to vibration.

The grid-like portion of the hopper is engaged with the article and thematerial is vibrated for a predetermined period of time. At thecessation of the vibration the hopper is rotated to shear away thematerial remaining in the hopper from the material which has beendispensed onto the article.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects and features of thepresent invention will be more readily understood from the followingdetailed description of specific embodiments thereof, when read inconjunction with the appended drawings in which:

FIG. 1 is an overall elevational view of the inventive dispensingapparatus;

FIG. 2 is an elevational view, with various portions removed forpurposes of clarity, illustrating the inventive dispensing apparatus ofFIG. 1;

FIG. 3 is a view of a lower portion of the apparatus of FIG. 2 withadditional portions removed for purposes of clarity;

FIGS. 4 through 8 are sectional views taken along the lines 4--4 of FIG.3 illustrating a sequence of steps employed by the apparatus of FIG. 1to accomplish a desired dispensing of material onto an article;

FIG. 9 is a sectional view taken along the lines 99 of FIG. 3 showing adesirable arrangement of wires forming a bottom of the apparatus of FIG.2;

FIG. 10 is a sectional view taken along the lines 10-10 of FIG. 3showing the wires of FIG. 9 at a location further from the center of theapparatus;

FIG. 11 is a sectional view of the apparatus of FIG. 2 taken along theline 111l showing a rotating mechanism; and

FIG. 12 is an illustration ofa cam profile taken along the lines 12-12of FIG. 11.

DETAILED DESCRIPTION Illustratively, the invention is described inconnection with dispensing viscous paste electrolyte onto battery grids.However, it is to be understood that this is only for purposes ofexplanation and that the invention has utility in dispensing variousother materials.

Referring now to FIG. 1 there is shown one embodiment of the invention,a dispensing machine, designated generally by the numeral'20'. Themachine 20 is positioned below a bulk feeder 22 which operates through aconventional level control system (not shown) to maintain apredetermined level of battery paste 21 within the dispensing machine20. Battery grids 24 are successively indexed to a position beneath thedispensing machine 20 on a linear conveyor, designated generally by thenumeral 26.

GENERAL OPERATION A cycle of operation begins when one of the grids 24is positioned beneath the holder mechanism 20. A dispensing hopper orcup, designated generally by the numeral 28, containing the batterypaste 21 is'lowered into engagement with the grid 24, as shown in FIGS.2, 3 and 4. After the cup 28 is engaged with the grid 24, a conventionalpneumatic vibrator 32 (FIG. 3) is actuated with a valve 33. Thevibrational energy of the vibrator 32 is principally coupled to thebattery paste 21 through coupling rods 34. Vibratory energy is alsointroduced through the body of the cup 28. As the paste 21 is vibrated,it flows out, as shown in FIG. 5, between strand-like members or wires36 which form a grid-like bottom for the cup 28.

The grid 24 is supported on the conveyor 26 with a layer of conventionalfilter paper 37 between the grid and the conveyor. The filter paper 37permits air to be expelled out of the grid 24 and through holes in theconveyor 26 during the paste dispensing process.

After a predetermined amount of time, the vibrator 32 is turned off andthe flow of the'paste 21 through the spaces between the wires 36 stops.The cup 28 is then rotated approximately As a result of the rotation,that portion of the paste 21 which is partially out of the cup 28 butnot fully in the grid 24 is sheared by the wires 36. This shearingaction is illustrated in FIG. 6.

After the shearing is completed, the cup 28 is raised away slightly fromthe surface of the grid 24, as shown in FIG. 7. Spring retaining members38 (FIG. 1) remain in contact with the grid 24 assuring that the gridremains in place against the conveyor 26 during the initial lifting ofthe cup 28.

FIG. 8 illustrates the cup 28 lifted completely away from the grid 24and the conveyor 26 thus representing a completion of a dispensingcycle. There is sufficient clearance between the cup 28 and the grid 24to permit removal of the grid and replacement with a subsequent grid inanticipation of another dispensing cycle.

DISPENSING CUP DESIGN The cup 28 (FIG. 2) is constructed of acylindrical shell 40, and a vibrator support member 42, which issuspended by the wires 36 which are oriented radially from a centersupport member 44 to the shell 40. The spacing between the wires 36 isextremely important. The spacing must be sufficiently small so that thepaste 2] does not flow between the wires when the cup is held in astatic state. The wires 36, however, must be far enough apart so thatwhen the vibrator 32 imparts vibrational energy to the paste 21 thereresults a desired flow of the paste through the wires.

It is also desirable to achieve substantially equal spacing betweenadjacent ones of the wires 36 across the entire bottom area of the cup28. Such equality of spacing is achieved by arranging alternate ones ofthe wires 36 on two different planes.

As shown in FIG. 9, the center support member 44 is provided with shortslots 46 and long slots 48. The long and short slots alternate with oneanother around the support member 44. When FIG. 9 is compared with FIG.10, it can be seen that a spacing d between adjacent wires issubstantially the same. Even though the lateral distance between thewires 36 is greater near the outer edge of the cup 28, the verticaldistance between the wires diminishes near the edge. The net result ofthe changes in distance is balanced to achieve a zero effect on thecritical dimension d. The dimension d is, of course, representative ofthe space through which the paste 21 must flow. The paste 21, therefore,flows out of the cup 28 at substantially the same rate across the entirebottom area of the cup.

By way of example, it has been found that a cup having an insidediameter of approximately 11 inches and a paste level of approximatelyone inch will properly dispense battery paste, such as tetra-basic leadsulfate (4PbOPbSO onto battery grids of the type described in U.S. Pat.No. 3,434,883 issued to L. D. Babusci et al. on Mar. 25, 1969. In theparticular exemplary dispensing cup, the bottom of the cup was formed of64 wires having a diameter of 0.030 inch. The difference in lengthbetween the short slots 46 and the long slots 48 was approximately 0.375inch and the center member 44 had a three inch diameter.

Vibrating the cup 28 at a frequency of approximately 10,000cycles/minute for a period of ten seconds was sufficient to dispense 21cubic inches of the paste 21.

VERTICAL MOVEMENT OF DISPENSING CUP FIG. 2 illustrates a desirablemechanical arrangement for moving the cup 28 vertically to alternatelyengage and disengage the cup with successive ones of the grids 24. Thecup 28 is mounted to the end of a support sleeve 50. The sleeve 50 isarranged to move slideably and rotatably within a bearing unit 52. A topend of the sleeve 50 is connected to a cylinder actuation plate 54. Theplate 54 is, of course, connected to the piston rod 56 of the cylinders30.

Also engaged with the plate 54 are two alignment rods 58. The alignmentrods are arranged to move slideably through alignment bearing assemblies60. At the lower end of each of the rods 58 there is provided a locatorplug 62.

A spring supporting plate 64 is slideably engaged with the alignmentrods 58. The plate 64 is spring biased away from the bearing assemblies60 with compression springs 66. The plate 64 is utilized to support thesprings 38 which hold the grid 24 in intimate contact with the conveyor26.

When the cup assembly 28 is lowered, the plugs 62 at the ends of therods 58 are the first components to engage with the conveyor 26. Theplugs are provided with tapered ends 68 which enter alignment holes 70on the conveyor 26. This assures that the grid 24 is precisely locatedon the center line of the cup 28.

As downward motion continues, the springs 38 mounted on the plate 64become engaged with the grid 24 thus clamping the grid firmly againstthe conveyor 26. Further downward motion begins compressing the springs66 and permitting relative motion between the cup 28 and the plate 64which effectively results in the cup being intimately engaged with thegrid 24.

During disengaging motion, the cup 28 and the alignment rods 58 areraised by the cylinders 30 until the 10- cator plug 62 becomes engagedwith the plate 64. After such engagement the plate 64 is also carriedupwardly with the cup 28.

SHEARING AND DISENGAGEMENT MECHANISM Referring now to FIGS. 11, 12 andthe upper portion of FIG. 2, there is illustrated a mechanism by whichthe shearing and initial disengagement steps of FIGS. 6 and 7 areaccomplished. The sleeve 50 is provided with a cam ring 72 at the topend thereof. The cam ring 72 is held to the plate 54 by a plurality ofcam followers 74. A cylinder 76 is mounted on the plate 54 in such a waythat actuation of the cylinder causes rotation of the cam ring 72 andthe connected sleeve 50 and cup 28.

When it is desired to shear the paste 21 and initially disengage the cup28 from the grid 24, the cylinder 76 is actuated. The cam ring 72 isprovided with slot profiles therein which are illustrated in FIG. 12.During 15 of rotation of the ring, the cup 28 retains its engagedvertical position and simple shearing takes place as shown in FIG. 6.During a subsequent 15 of rotation, the cam ring 72 is lifted at auniform rate to a distance of approximately one-fourth inch as shown inFIG. 7. The combined shearing and initial lifting are suitable todisengage the cup 28 cleanly from the grid 24 into which paste 21 hasbeen dispensed.

It should be noted that throughout the shearing and lifting caused bythe actuation of the cylinder 76, there is no motion of the plate 64which holds the springs 38 down against the grid 24. Thus, there is notendency for the grid 24 to rise up with the cup 28.

Although certain embodiments of the invention have been shown in thedrawings and described in the specification, it is to be understood thatthe invention is not limited thereto, is capable of modification and canbe arranged without departing from the spirit and scope of theinvention.

What is claimed is:

1. Apparatus for dispensing material, which comprises:

a holder for the material, said holder having openings therein formed bya plurality of strand-like members, the openings being small enough topreclude the free flow of the material therethrough when the material isstatically held, but with said openings being large enough to permit theflow of said material therethrough when vibratory energy is applied tothe material;

means for applying vibratory energy to the material to flow the materialthrough the openings; and

means, operable at the cessation of the vibratory energy, for moving theholder relative to the material that has flowed through the openings toshear such flowed material.

2. The apparatus of claim 1, wherein the holder is cylindrical and theopenings are formed by the strand-like members being radially oriented.

3. Apparatus for dispensing viscous material, which comprises:

a hopper for the viscous material, said hopper having a grid bottom withopenings therein formed by a plurality of wires disposed in at least twodifferent planes, the openings being small enough to preclude the freeflow of the material therethrough when the material is statically heldin the hopper, but with said openings being large enough to permit theflow of said material therethrough when the material is subjected tovibration;

means for vibrating the material toflow the material through theopenings of the grid bottom of the hopper; and

means, operable at the cessation of the vibration, for

moving the grid bottom relative to the material that has flowed throughthe openings to shear such flowed material.

4. The apparatus of claim 3 wherein the vibrating means is coupled tothe viscous material with rods that extend into the material internallyof the hopper.

5. The apparatus of claim 3 wherein the hopper is cylindrical and thewires are radially oriented and spaced so that the distance between thewires is substantially the same across the entire area of the bottom.

6. A method of dispensing a material comprising the steps of:

holding a quantity of the material in a hopper having openings thereinformed by a plurality of strandlike members in at least two differentplanes, the openings being small enough to preclude the free flow of thematerial therethrough;

applying vibratory energy to the material to flow it through theopenings in the hopper; and

moving the hopper, after the cessation of the vibratory energy, to movethe strand-like members relative to the material that has flowed throughthe openings to shear such flowed material.

7. The apparatus of claim 3, wherein the moving means rotate the hopperabout an axis extending perpendicularly through the grid bottom to causethe wires to shear away the material that has flowed through theopenings.

1. Apparatus for dispensing material, which comprises: a holder for thematerial, said holder having openings therein formed by a plurality ofstrand-like members, the openings being small enough to preclude thefree flow of the material therethrough when the material is staticallyheld, but with said openings being large enough to permit the flow ofsaid material therethrough when vibratory energy is applied to thematerial; means for applying vibratory energy to the material to flowthe material through the openings; and means, operable at the cessationof the vibratory energy, for moving the holder relative to the materialthat has flowed through the openings to shear such flowed material. 2.The apparatus of claim 1, wherein the holder is cylindrical and theopenings are formed by the strand-like members being radially oriented.3. Apparatus for dispensing viscous material, which comprises: a hopperfor the viscous material, said hopper having a grid bottom with openingstherein formed by a plurality of wires disposed in at least twodifferent planes, the openings being small enough to preclude the freeflow of the material tHerethrough when the material is statically heldin the hopper, but with said openings being large enough to permit theflow of said material therethrough when the material is subjected tovibration; means for vibrating the material to flow the material throughthe openings of the grid bottom of the hopper; and means, operable atthe cessation of the vibration, for moving the grid bottom relative tothe material that has flowed through the openings to shear such flowedmaterial.
 4. The apparatus of claim 3 wherein the vibrating means iscoupled to the viscous material with rods that extend into the materialinternally of the hopper.
 5. The apparatus of claim 3 wherein the hopperis cylindrical and the wires are radially oriented and spaced so thatthe distance between the wires is substantially the same across theentire area of the bottom.
 6. A method of dispensing a materialcomprising the steps of: holding a quantity of the material in a hopperhaving openings therein formed by a plurality of strand-like members inat least two different planes, the openings being small enough topreclude the free flow of the material therethrough; applying vibratoryenergy to the material to flow it through the openings in the hopper;and moving the hopper, after the cessation of the vibratory energy, tomove the strand-like members relative to the material that has flowedthrough the openings to shear such flowed material.
 7. The apparatus ofclaim 3, wherein the moving means rotate the hopper about an axisextending perpendicularly through the grid bottom to cause the wires toshear away the material that has flowed through the openings.